US1796868A

US1796868A - Grate bar

Info

Publication number: US1796868A
Application number: US330093A
Authority: US
Inventors: Hagedorn Carl; John W Hagedorn
Original assignee: Individual
Current assignee: Individual
Priority date: 1929-01-03
Filing date: 1929-01-03
Publication date: 1931-03-17
Anticipated expiration: 1948-03-17

Description

March 17, 1931. Q HAGEDQRN T' 1,796,868

GRATE BAR Filed Jan. 3. 1929 (MRI. HAG'EDOR/V dOlf/V MHAGEDOR/V WWMM Fatented Mar. 17, 1931 umren STATES PATENT OFFICE GR-ATE BAR.

Application filed January 3, 1929.

Our present invention relates to improvements in grate bars for use in furnaces of various types, and involving the use of interchangeable, renewable, fuel plates with the supporting parts of the bars. The primary obJect of the invention is to render more durable the grate bars and extend their pe riod of use by providing venting for the circulation of air currents through the 'different parts of the grate bars so that the heat may uniformly be distributed to insure uniform expansion and contract-ion and thus avoid warping or burning of the bars. Means are also provided for relieving the grate bars of excess heat, by the circulation of water through the bars, thus conveying excess heat from the bars and cooling them to such an extent as to prevent warping and burning under excessive heat in the furnace. The invention consists in certain novel combinations and arrangements of parts as will hereinafter be more fully set forth and claimed. In the accompanying drawings we have shown one complete example, and a :4 slight modification thereof, of the physical embodiment of our invention, wherein the parts are combined and arranged according to modes we have thus far devised for the practical application of the principles of our invention, and the grate bars exemplified have successfully and extensively been used, and are now being used in actual practice.

Figure 1 is a view in side elevation of one of the grate bars supported between furnace walls and equipped with the water cooling pipes. Figure 2 is a. perspective view of one of the bars with the fuel plates removed, and broken away for convenience of illustration.

Figure 3 is a longitudinal sectional view of a grate bar and its fuel plates, as at line 3-3 of Figure 2.

Figure 4-.is a perspective View of one of the fuel plates, inverted, used in Figures 1 and 3. Figure 5 is a transverse vertical sectional view at line 55 of Figure 1. Figure 6 is a perspective View of a modified form of fuel plate, inverted, and Figure 7 is a sectional view, similar to Figure 5, but with the water pipes omitted and a modified form of fuel plate illustrated, as shown in Figure 6.

Serial No. 330,993,

In the preferred form of the invention we have shown in Figure l a usual front Wall I, and rear wall or arch 2, of a furnace, the wall ora-rch-2 being cut away in its front face at 3 to allow for expansion of the grate bars under heat in the furnace. At the front of the furnace a supporting ledge 4L or other suitable support is provided, and a complemen-tary support 5 is used on the front of the arch'or rearwall, between which supports the grate bars are supported to; permit longitudinal expansion and contraction.

Each grate bar includes-the hollow member having spaced side. walls 6 and: 7 that are, joined by the integral intermediate webs 8', and the end bars 9, the latter having lateral lugs 10 to space adjoining bars'for the formationof vertical slots between the bars to perunit venting of air currents through the grate. p

' Inthet'op edge of'eachof the-side walls ofthe grate we fashion a longitudinally extending groove 11,, that is, semi-circular in cross section, and ext-endsfrom endtoe-nd? ofthe gratebar, for the reception of water pipes 12 that lie in the grooves; Fhese pipes are connected at their opposite ends to headers or manifolds 13 and Matthe remote faces of'thefront and rear walls of the furnace, and the pipes andheaders form acirculation system for- Water throughout the whole grate for cooling the latter-or for relieving excessiveheat in the bars. The water issupplied to the system through iinlet -pi5pe15 at one endand an out.- let pipe-1T is shown at the other end of the system, a control valve 16 being used in the V inlet pipe for control of the water flowing through the coolingcoils of the grate.

In combinationwith the grate bar we use removable, interchangeable, and renewable fuel plates 18, three of which are shown in- Figure 1, but of" course; more plates are used: on alongergrate bar. These plates are'concave-convex'or arched with roundedtops, and are provided with holes 19 for venting, and at thei nundersides each plate isprovided with longitudinally extending grooves. 20,. semi; circular. in cross section and; complementary tathe grooves; in the: top, edges ot the; walls of the; ban, Between. the grooved: edges of the bar and the grooved edges of the plates the water pipes are enclosed and the pipes provide retaining means for the plates to hold them against lateral displacement. The fuel plates also have side lugs 21 at their opposite ends, complementary to the lugs 10 at the sides of the ends of the bars, and designed to provide for venting slots in the grate between adjoining grate bars.

On the under face of each fuel plate are a pair of

integral lugs

22 and 23 extending transversely of the plate, one lug as 22, being located adjacent an end of the plate while the other lug is located a greater distance from the opposite end of the plate. The length of these bottom lugs is such as to have the lugs fit in between the spaced walls 6 and 7 of the grate and allow for expansion.

In actual practice and extended use of the grate bars with the cooling system of water circulation through the pipes we find that the grate bars are more durable and that they have a greater resistance against warping, burning, or deformation of the fuel plates due to the heat of the furnace. The water pipes are so situated as not to interfere with ventilation through the grate and their enclosure between the grate bars and the fuel plates protects and shields them from direct contact with flames, or with ashes and fuel.

I Vhen the presence of the cooling water pipes is not necessary, the fuel plates 18 may be replaced by interchangeable plates 24 from which the semi-circular grooves are omitted, but which are fashioned at their under edges with transversely extending bosses 25 which rest upon the grooved edges at the tops of the sidewalls 6 and 7 of the grate bar walls, as indicated in Figures 6 and 7 wherethis modified form of the fuel plates is shown. v

It will be noted that the transverse lugs 22 are nearer an end of the fuel plate than the lugs 23, and this arrangement of lugs in the series of plates, as in Figures 1 and 3, allows for longitudinal expansion of the plates in the same direction, that is, to the right as in Figure 1. The location of the lugs at difierent distances from their adjoining edges or ends also prevents likelihood of the'plate expanding to such an extent as to wedge the lugs between adjoining intermediate webs or between intermediate webs and adjoining end webs. The fuel plates when worn may thus readily be removed and replaced by fresh ones, the transverse lugs at the under side of the plates being arranged in the same relative positions in each fuel plate. 7 p

Having thus fully described our invention, what we claim as new and desire to secure by Letters Patent is In a grate bar the combination with spaced side walls having end bars and intermediate tures.

" CARL HAGEDORN.

JOHN IV. HAGEDORN.